I agree with you, but only so far. I have done some touching up on my in-game photos, but it doesn't take much for them to start to look really processed.

One of the things that doesn't bother me about the in-game shots is the slightly softer focus of them. I actually prefer that to seeing all the hard edges of the models. But it's not just a softer focus in some of the pics... there's that hint of compression (mind you, it's really just a hint, and I'd hardly be bothered by it in someone else's pics - when I say I'm picky about images, I'm almost always talking about composition).